refactor(tiptap): simplify first block selection check (#3842)

Author: ComputelessComputer

packages/tiptap/src/editor/index.tsx

@@ -93,17 +93,17 @@ const Editor = forwardRef<{ editor: TiptapEditor | null }, EditorProps>(
           const isAtStart = state.selection.$head.pos === 0;
 
           const $head = state.selection.$head;
-          const depth = $head.depth;
           let isInFirstBlock = false;
 
-          for (let d = depth; d > 0; d--) {
-            const node = $head.node(d);
-            if (node.type.name === "doc") continue;
-            const parentNode = $head.node(d - 1);
-            if (parentNode.type.name === "doc") {
-              isInFirstBlock = parentNode.firstChild === node;
-              break;
-            }
+          let node = state.doc.firstChild;
+          let firstTextBlockPos = 0;
+          while (node && !node.isTextblock) {
+            firstTextBlockPos += 1;
+            node = node.firstChild;
+          }
+
+          if (node) {
+            isInFirstBlock = $head.start($head.depth) === firstTextBlockPos + 1;
           }
 
           if (